kernel26-xen/patches-2.6.25-r1/1046-2.6.25-xen-blkback-cdrom.patch

Subject: CDROM removable media-present attribute plus handling code
From: plc@novell.com
Patch-mainline: obsolete
References: 159907

Index: head-2007-10-15/drivers/xen/blkback/Makefile
===================================================================
--- head-2007-10-15.orig/drivers/xen/blkback/Makefile	2007-10-22 10:47:58.000000000 +0200
+++ head-2007-10-15/drivers/xen/blkback/Makefile	2007-08-07 10:14:50.000000000 +0200
@@ -1,3 +1,3 @@
 obj-$(CONFIG_XEN_BLKDEV_BACKEND) := blkbk.o
 
-blkbk-y	:= blkback.o xenbus.o interface.o vbd.o
+blkbk-y	:= blkback.o xenbus.o interface.o vbd.o cdrom.o
Index: head-2007-10-15/drivers/xen/blkback/cdrom.c
===================================================================
--- /dev/null	1970-01-01 00:00:00.000000000 +0000
+++ head-2007-10-15/drivers/xen/blkback/cdrom.c	2007-08-07 10:14:50.000000000 +0200
@@ -0,0 +1,169 @@
+/******************************************************************************
+ * blkback/cdrom.c
+ *
+ * Routines for managing cdrom watch and media-present attribute of a
+ * cdrom type virtual block device (VBD).
+ *
+ * Copyright (c) 2003-2005, Keir Fraser & Steve Hand
+ * Copyright (c) 2007       Pat Campbell
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation; or, when distributed
+ * separately from the Linux kernel or incorporated into other
+ * software packages, subject to the following license:
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this source file (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify,
+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
+ * and to permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include "common.h"
+
+#undef DPRINTK
+#define DPRINTK(_f, _a...)			\
+	printk("(%s() file=%s, line=%d) " _f "\n",	\
+		 __PRETTY_FUNCTION__, __FILE__ , __LINE__ , ##_a )
+
+
+#define MEDIA_PRESENT "media-present"
+
+static void cdrom_media_changed(struct xenbus_watch *, const char **, unsigned int);
+
+/**
+ * Writes media-present=1 attribute for the given vbd device if not
+ * already there
+ */
+static int cdrom_xenstore_write_media_present(struct backend_info *be)
+{
+	struct xenbus_device *dev = be->dev;
+	struct xenbus_transaction xbt;
+	int err;
+    int media_present;
+
+	DPRINTK(" ");
+
+	err = xenbus_scanf(XBT_NIL, dev->nodename, MEDIA_PRESENT, "%d",
+			   &media_present);
+	if ( 0 < err) {
+		DPRINTK("already written err%d", err);
+		return(0);
+	}
+    media_present = 1;
+
+again:
+	err = xenbus_transaction_start(&xbt);
+	if (err) {
+		xenbus_dev_fatal(dev, err, "starting transaction");
+		return(-1);
+	}
+
+	err = xenbus_printf(xbt, dev->nodename, MEDIA_PRESENT, "%d", media_present );
+	if (err) {
+		xenbus_dev_fatal(dev, err, "writing %s/%s",
+			 dev->nodename, MEDIA_PRESENT);
+		goto abort;
+	}
+	err = xenbus_transaction_end(xbt, 0);
+	if (err == -EAGAIN)
+		goto again;
+	if (err)
+		xenbus_dev_fatal(dev, err, "ending transaction");
+    return(0);
+ abort:
+	xenbus_transaction_end(xbt, 1);
+    return(-1);
+}
+
+/**
+ *
+ */
+int cdrom_is_type(struct backend_info *be)
+{
+    DPRINTK( "type:%x", be->blkif->vbd.type );
+    if ( be->blkif->vbd.type & VDISK_CDROM && be->blkif->vbd.type & GENHD_FL_REMOVABLE){
+	    return(1);
+	}
+	return(0);
+}
+
+/**
+ *
+ */
+void cdrom_add_media_watch(struct backend_info *be)
+{
+	struct xenbus_device *dev = be->dev;
+	int err;
+
+    DPRINTK( "nodename:%s", dev->nodename);
+    if (cdrom_is_type(be)) {
+        DPRINTK("is a cdrom");
+        if ( cdrom_xenstore_write_media_present(be) == 0 ) {
+            DPRINTK( "xenstore wrote OK");
+	        err = xenbus_watch_path2(dev, dev->nodename, MEDIA_PRESENT,
+		        &be->backend_cdrom_watch, cdrom_media_changed);
+		    if (err) {
+			    DPRINTK( "media_present watch add failed" );
+		    }
+        }
+	}
+}
+
+/**
+ * Callback received when the "media_present" xenstore node is changed
+ */
+static void cdrom_media_changed(struct xenbus_watch *watch,
+			    const char **vec, unsigned int len)
+{
+	int err;
+	unsigned media_present;
+	struct backend_info *be
+		= container_of(watch, struct backend_info, backend_cdrom_watch);
+	struct xenbus_device *dev = be->dev;
+
+	DPRINTK(" ");
+
+    if ( !(cdrom_is_type(be))) {
+		DPRINTK("callback not for a cdrom" );
+		return;
+	}
+
+	err = xenbus_scanf(XBT_NIL, dev->nodename, MEDIA_PRESENT, "%d",
+			   &media_present);
+	if (err == 0 || err == -ENOENT) {
+		DPRINTK("xenbus_read of cdrom media_present node error:%d",err);
+		return;
+	}
+
+	if (media_present == 0) {
+	    vbd_free(&be->blkif->vbd);
+	}
+	else {
+		char *p = strrchr(dev->otherend, '/') + 1;
+		long handle = simple_strtoul(p, NULL, 0);
+
+        if (be->blkif->vbd.bdev == NULL) {
+		    err = vbd_create(be->blkif, handle, be->major, be->minor,
+				     (NULL == strchr(be->mode, 'w')));
+		    if (err) {
+			    be->major = be->minor = 0;
+			    xenbus_dev_fatal(dev, err, "creating vbd structure");
+			    return;
+		    }
+		}
+	}
+}
Index: head-2007-10-15/drivers/xen/blkback/common.h
===================================================================
--- head-2007-10-15.orig/drivers/xen/blkback/common.h	2007-10-19 16:00:18.000000000 +0200
+++ head-2007-10-15/drivers/xen/blkback/common.h	2007-10-19 16:03:26.000000000 +0200
@@ -96,6 +96,17 @@ typedef struct blkif_st {
 	grant_ref_t    shmem_ref;
 } blkif_t;
 
+struct backend_info
+{
+	struct xenbus_device *dev;
+	blkif_t *blkif;
+	struct xenbus_watch backend_watch;
+	struct xenbus_watch backend_cdrom_watch;
+	unsigned major;
+	unsigned minor;
+	char *mode;
+};
+
 blkif_t *blkif_alloc(domid_t domid);
 void blkif_disconnect(blkif_t *blkif);
 void blkif_free(blkif_t *blkif);
@@ -136,4 +147,8 @@ int blkif_schedule(void *arg);
 int blkback_barrier(struct xenbus_transaction xbt,
 		    struct backend_info *be, int state);
 
+/* cdrom media change */
+int cdrom_is_type(struct backend_info *be);
+void cdrom_add_media_watch(struct backend_info *be);
+
 #endif /* __BLKIF__BACKEND__COMMON_H__ */
Index: head-2007-10-15/drivers/xen/blkback/vbd.c
===================================================================
--- head-2007-10-15.orig/drivers/xen/blkback/vbd.c	2007-10-22 10:47:58.000000000 +0200
+++ head-2007-10-15/drivers/xen/blkback/vbd.c	2007-08-07 10:14:50.000000000 +0200
@@ -106,6 +106,9 @@ int vbd_translate(struct phys_req *req, 
 	if ((operation != READ) && vbd->readonly)
 		goto out;
 
+	if (vbd->bdev == NULL)
+		goto out;
+
 	if (unlikely((req->sector_number + req->nr_sects) > vbd_sz(vbd)))
 		goto out;
 
Index: head-2007-10-15/drivers/xen/blkback/xenbus.c
===================================================================
--- head-2007-10-15.orig/drivers/xen/blkback/xenbus.c	2007-10-22 10:50:20.000000000 +0200
+++ head-2007-10-15/drivers/xen/blkback/xenbus.c	2007-10-22 10:50:35.000000000 +0200
@@ -28,16 +28,6 @@
 	pr_debug("blkback/xenbus (%s:%d) " fmt ".\n",	\
 		 __FUNCTION__, __LINE__, ##args)
 
-struct backend_info
-{
-	struct xenbus_device *dev;
-	blkif_t *blkif;
-	struct xenbus_watch backend_watch;
-	unsigned major;
-	unsigned minor;
-	char *mode;
-};
-
 static void connect(struct backend_info *);
 static int connect_ring(struct backend_info *);
 static void backend_changed(struct xenbus_watch *, const char **,
@@ -183,6 +173,12 @@ static int blkback_remove(struct xenbus_
 		be->backend_watch.node = NULL;
 	}
 
+	if (be->backend_cdrom_watch.node) {
+		unregister_xenbus_watch(&be->backend_cdrom_watch);
+		kfree(be->backend_cdrom_watch.node);
+		be->backend_cdrom_watch.node = NULL;
+	}
+
 	if (be->blkif) {
 		blkif_disconnect(be->blkif);
 		vbd_free(&be->blkif->vbd);
@@ -331,6 +327,9 @@ static void backend_changed(struct xenbu
 
 		/* We're potentially connected now */
 		update_blkif_status(be->blkif);
+
+		/* Add watch for cdrom media status if necessay */
+		cdrom_add_media_watch(be);
 	}
 }
 
1	Subject: CDROM removable media-present attribute plus handling code
2	From: plc@novell.com
3	Patch-mainline: obsolete
4	References: 159907
5
6	Index: head-2007-10-15/drivers/xen/blkback/Makefile
7	===================================================================
8	--- head-2007-10-15.orig/drivers/xen/blkback/Makefile 2007-10-22 10:47:58.000000000 +0200
9	+++ head-2007-10-15/drivers/xen/blkback/Makefile 2007-08-07 10:14:50.000000000 +0200
10	@@ -1,3 +1,3 @@
11	obj-$(CONFIG_XEN_BLKDEV_BACKEND) := blkbk.o
12
13	-blkbk-y := blkback.o xenbus.o interface.o vbd.o
14	+blkbk-y := blkback.o xenbus.o interface.o vbd.o cdrom.o
15	Index: head-2007-10-15/drivers/xen/blkback/cdrom.c
16	===================================================================
17	--- /dev/null 1970-01-01 00:00:00.000000000 +0000
18	+++ head-2007-10-15/drivers/xen/blkback/cdrom.c 2007-08-07 10:14:50.000000000 +0200
19	@@ -0,0 +1,169 @@
20	+/******************************************************************************
21	+ * blkback/cdrom.c
22	+ *
23	+ * Routines for managing cdrom watch and media-present attribute of a
24	+ * cdrom type virtual block device (VBD).
25	+ *
26	+ * Copyright (c) 2003-2005, Keir Fraser & Steve Hand
27	+ * Copyright (c) 2007 Pat Campbell
28	+ *
29	+ * This program is free software; you can redistribute it and/or
30	+ * modify it under the terms of the GNU General Public License version 2
31	+ * as published by the Free Software Foundation; or, when distributed
32	+ * separately from the Linux kernel or incorporated into other
33	+ * software packages, subject to the following license:
34	+ *
35	+ * Permission is hereby granted, free of charge, to any person obtaining a copy
36	+ * of this source file (the "Software"), to deal in the Software without
37	+ * restriction, including without limitation the rights to use, copy, modify,
38	+ * merge, publish, distribute, sublicense, and/or sell copies of the Software,
39	+ * and to permit persons to whom the Software is furnished to do so, subject to
40	+ * the following conditions:
41	+ *
42	+ * The above copyright notice and this permission notice shall be included in
43	+ * all copies or substantial portions of the Software.
44	+ *
45	+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
46	+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
47	+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
48	+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
49	+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
50	+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
51	+ * IN THE SOFTWARE.
52	+ */
53	+
54	+#include "common.h"
55	+
56	+#undef DPRINTK
57	+#define DPRINTK(_f, _a...) \
58	+ printk("(%s() file=%s, line=%d) " _f "\n", \
59	+ __PRETTY_FUNCTION__, __FILE__ , __LINE__ , ##_a )
60	+
61	+
62	+#define MEDIA_PRESENT "media-present"
63	+
64	+static void cdrom_media_changed(struct xenbus_watch , const char *, unsigned int);
65	+
66	+/**
67	+ * Writes media-present=1 attribute for the given vbd device if not
68	+ * already there
69	+ */
70	+static int cdrom_xenstore_write_media_present(struct backend_info *be)
71	+{
72	+ struct xenbus_device *dev = be->dev;
73	+ struct xenbus_transaction xbt;
74	+ int err;
75	+ int media_present;
76	+
77	+ DPRINTK(" ");
78	+
79	+ err = xenbus_scanf(XBT_NIL, dev->nodename, MEDIA_PRESENT, "%d",
80	+ &media_present);
81	+ if ( 0 < err) {
82	+ DPRINTK("already written err%d", err);
83	+ return(0);
84	+ }
85	+ media_present = 1;
86	+
87	+again:
88	+ err = xenbus_transaction_start(&xbt);
89	+ if (err) {
90	+ xenbus_dev_fatal(dev, err, "starting transaction");
91	+ return(-1);
92	+ }
93	+
94	+ err = xenbus_printf(xbt, dev->nodename, MEDIA_PRESENT, "%d", media_present );
95	+ if (err) {
96	+ xenbus_dev_fatal(dev, err, "writing %s/%s",
97	+ dev->nodename, MEDIA_PRESENT);
98	+ goto abort;
99	+ }
100	+ err = xenbus_transaction_end(xbt, 0);
101	+ if (err == -EAGAIN)
102	+ goto again;
103	+ if (err)
104	+ xenbus_dev_fatal(dev, err, "ending transaction");
105	+ return(0);
106	+ abort:
107	+ xenbus_transaction_end(xbt, 1);
108	+ return(-1);
109	+}
110	+
111	+/**
112	+ *
113	+ */
114	+int cdrom_is_type(struct backend_info *be)
115	+{
116	+ DPRINTK( "type:%x", be->blkif->vbd.type );
117	+ if ( be->blkif->vbd.type & VDISK_CDROM && be->blkif->vbd.type & GENHD_FL_REMOVABLE){
118	+ return(1);
119	+ }
120	+ return(0);
121	+}
122	+
123	+/**
124	+ *
125	+ */
126	+void cdrom_add_media_watch(struct backend_info *be)
127	+{
128	+ struct xenbus_device *dev = be->dev;
129	+ int err;
130	+
131	+ DPRINTK( "nodename:%s", dev->nodename);
132	+ if (cdrom_is_type(be)) {
133	+ DPRINTK("is a cdrom");
134	+ if ( cdrom_xenstore_write_media_present(be) == 0 ) {
135	+ DPRINTK( "xenstore wrote OK");
136	+ err = xenbus_watch_path2(dev, dev->nodename, MEDIA_PRESENT,
137	+ &be->backend_cdrom_watch, cdrom_media_changed);
138	+ if (err) {
139	+ DPRINTK( "media_present watch add failed" );
140	+ }
141	+ }
142	+ }
143	+}
144	+
145	+/**
146	+ * Callback received when the "media_present" xenstore node is changed
147	+ */
148	+static void cdrom_media_changed(struct xenbus_watch *watch,
149	+ const char **vec, unsigned int len)
150	+{
151	+ int err;
152	+ unsigned media_present;
153	+ struct backend_info *be
154	+ = container_of(watch, struct backend_info, backend_cdrom_watch);
155	+ struct xenbus_device *dev = be->dev;
156	+
157	+ DPRINTK(" ");
158	+
159	+ if ( !(cdrom_is_type(be))) {
160	+ DPRINTK("callback not for a cdrom" );
161	+ return;
162	+ }
163	+
164	+ err = xenbus_scanf(XBT_NIL, dev->nodename, MEDIA_PRESENT, "%d",
165	+ &media_present);
166	+ if (err == 0 \|\| err == -ENOENT) {
167	+ DPRINTK("xenbus_read of cdrom media_present node error:%d",err);
168	+ return;
169	+ }
170	+
171	+ if (media_present == 0) {
172	+ vbd_free(&be->blkif->vbd);
173	+ }
174	+ else {
175	+ char *p = strrchr(dev->otherend, '/') + 1;
176	+ long handle = simple_strtoul(p, NULL, 0);
177	+
178	+ if (be->blkif->vbd.bdev == NULL) {
179	+ err = vbd_create(be->blkif, handle, be->major, be->minor,
180	+ (NULL == strchr(be->mode, 'w')));
181	+ if (err) {
182	+ be->major = be->minor = 0;
183	+ xenbus_dev_fatal(dev, err, "creating vbd structure");
184	+ return;
185	+ }
186	+ }
187	+ }
188	+}
189	Index: head-2007-10-15/drivers/xen/blkback/common.h
190	===================================================================
191	--- head-2007-10-15.orig/drivers/xen/blkback/common.h 2007-10-19 16:00:18.000000000 +0200
192	+++ head-2007-10-15/drivers/xen/blkback/common.h 2007-10-19 16:03:26.000000000 +0200
193	@@ -96,6 +96,17 @@ typedef struct blkif_st {
194	grant_ref_t shmem_ref;
195	} blkif_t;
196
197	+struct backend_info
198	+{
199	+ struct xenbus_device *dev;
200	+ blkif_t *blkif;
201	+ struct xenbus_watch backend_watch;
202	+ struct xenbus_watch backend_cdrom_watch;
203	+ unsigned major;
204	+ unsigned minor;
205	+ char *mode;
206	+};
207	+
208	blkif_t *blkif_alloc(domid_t domid);
209	void blkif_disconnect(blkif_t *blkif);
210	void blkif_free(blkif_t *blkif);
211	@@ -136,4 +147,8 @@ int blkif_schedule(void *arg);
212	int blkback_barrier(struct xenbus_transaction xbt,
213	struct backend_info *be, int state);
214
215	+/* cdrom media change */
216	+int cdrom_is_type(struct backend_info *be);
217	+void cdrom_add_media_watch(struct backend_info *be);
218	+
219	#endif /* __BLKIF__BACKEND__COMMON_H__ */
220	Index: head-2007-10-15/drivers/xen/blkback/vbd.c
221	===================================================================
222	--- head-2007-10-15.orig/drivers/xen/blkback/vbd.c 2007-10-22 10:47:58.000000000 +0200
223	+++ head-2007-10-15/drivers/xen/blkback/vbd.c 2007-08-07 10:14:50.000000000 +0200
224	@@ -106,6 +106,9 @@ int vbd_translate(struct phys_req *req,
225	if ((operation != READ) && vbd->readonly)
226	goto out;
227
228	+ if (vbd->bdev == NULL)
229	+ goto out;
230	+
231	if (unlikely((req->sector_number + req->nr_sects) > vbd_sz(vbd)))
232	goto out;
233
234	Index: head-2007-10-15/drivers/xen/blkback/xenbus.c
235	===================================================================
236	--- head-2007-10-15.orig/drivers/xen/blkback/xenbus.c 2007-10-22 10:50:20.000000000 +0200
237	+++ head-2007-10-15/drivers/xen/blkback/xenbus.c 2007-10-22 10:50:35.000000000 +0200
238	@@ -28,16 +28,6 @@
239	pr_debug("blkback/xenbus (%s:%d) " fmt ".\n", \
240	__FUNCTION__, __LINE__, ##args)
241
242	-struct backend_info
243	-{
244	- struct xenbus_device *dev;
245	- blkif_t *blkif;
246	- struct xenbus_watch backend_watch;
247	- unsigned major;
248	- unsigned minor;
249	- char *mode;
250	-};
251	-
252	static void connect(struct backend_info *);
253	static int connect_ring(struct backend_info *);
254	static void backend_changed(struct xenbus_watch , const char *,
255	@@ -183,6 +173,12 @@ static int blkback_remove(struct xenbus_
256	be->backend_watch.node = NULL;
257	}
258
259	+ if (be->backend_cdrom_watch.node) {
260	+ unregister_xenbus_watch(&be->backend_cdrom_watch);
261	+ kfree(be->backend_cdrom_watch.node);
262	+ be->backend_cdrom_watch.node = NULL;
263	+ }
264	+
265	if (be->blkif) {
266	blkif_disconnect(be->blkif);
267	vbd_free(&be->blkif->vbd);
268	@@ -331,6 +327,9 @@ static void backend_changed(struct xenbu
269
270	/* We're potentially connected now */
271	update_blkif_status(be->blkif);
272	+
273	+ /* Add watch for cdrom media status if necessay */
274	+ cdrom_add_media_watch(be);
275	}
276	}
277